This application is a continuation in part of U.S. utility patent application Ser. No. 10/683,889 which is a continuation in part of U.S. utility patent application Ser. No. 09/752,956.
My invention generally relates to combined intercropping of, and application of mulch to, commercial field crops. More particularly, my invention is a process in which annuals are planted in the fall to provide a green manure the following spring to intercropped commercial crops. My invention is intended for planters, farmers and gardeners of all specialties, and to all kinds, sizes and complexities of farming enterprises.
‘Intercropping’ is generally defined as the planting of a fast growing crop between alternating rows of a slow growing crop. My new method incorporates the commercially successful tillage system of the United States, particularly in the midwestern and prairie states. My method also incorporates the beneficial ecological effect of growing a commercial annual legume with corn, as well as incorporation of an annual green manure crop such as wheat and buckwheat.
My preferred method of intercropping comprises strip cropping corn and soybeans with subsequent application of green manure to the soil, and a layer of mulch upon the topsoil surface. My method does not require pesticides, herbicides or artificial fertilizers for healthy crops, nor to obtain an effective ground cover and subsoil root network with an effective moisture canopy and windbreak.
Moreover, my invention provides a kindlier developmental period for both soybean and corn seedlings through its microclimate effect. Annual green manure plants such as buckwheat remain uncut until tillage and seeding of the commercial crop in early spring. Green manure provides nutrients for a seedling commercial spring crop, as well as a welcome mulch ground cover during the early growing season. My treated soil also accumulates soil nutrients with yearly use, thereby increasing land productivity. Tilling soil more than once a year may expose soil to air and decreases nutrients and fallow soil. As a result, tilling soil and leaving it without a mulch covering is discouraged.
Green manure plants combined with organic residue from deceased crops contains desiccated soybean roots and nitrogen nodules which remain intact in the soil. During the winter months, the intact root systems of these nonviable soybean and corn (and viable wheat) also function as ground cover and subsoil root retention system. In this manner, intact soybean and corn roots provide a physical soil network for the no till planting of a green manure crop (for example wheat and buckwheat grass) in the fall or early spring as the case may be. For example, wheat and buckwheat are planted in the fall or early spring, and are subsequently tilled into the soil as green manure while green and viable.
The farmer synchronizes planting (seeding) of the intercropped commercial plants with tilling the green manure plants into the soil. My process also provides: a reliable source of soluble nitrogenous and phosphorus compounds in the soil, additional humus and retention of soil, and an economical growth with cutting of green manure for a mulch covering.
U.S. Pat. No. 6,331,585 B1 (Williams) discloses an intercropping method in which soybeans are seeded within corn in an alternating predetermined pattern over an entire field. This method is adjustable to other crop and legume combinations, as well as larger commercial sized operations and small home gardens and fields. For best results the corn and soybeans are seeded at the same time in early May. The corn and soybeans subsequently create a micro-climate of humidity, as well as a comprehensive root system and ground cover. These features ameliorate drought and erosion during the entire year. Another advantage is use of conservation tillage which augments ecological long term advantages of intercropping commercial annual grains and legumes. However, no particular prior art farm implements or mulching step are provided for this intercropping method.
There are prior art approaches to planting annual grain crops in a single growing area. U.S. Pat. No. 5,140,917 (Swanson) describes a method and apparatus for seeding agricultural crops. Using this method, seeds are placed in residue free rows which are closely aligned with bands of deeply placed fertilizer. The plants from each seed are claimed to access more than one deep band of fertilizer. There is no intercropping component to Swanson's model, and Swanson requires increased fertilizer and seed costs for optimum results.
European Application 0132521 (Hilmer) describes intercropping with two or more crops on one piece of land per seasonal growing year. Hilmer used a grass/grain cluster/per row or a modular cluster row planter upon a slope contour.
U.S. Pat. No. 4,084,522(Younger) describes a method by which soybean seeds are sown into a standing grain crop (e.g. wheat). When the grain crop is ripe, it is harvested at a height which is slightly greater than the height of the partially grown soybeans. Unlike my process, however, in Younger's model the wheat is planted first, while corn and soybeans are planted considerably later during the same growing season. Moreover, there is no specialized seed application in Younger's method.
U.S. Pat. No. 6,009,955 (Tarver III) is based upon the size and shape of furrows created by a modified harvesting machine. The planter creates these furrows just prior to planting or during the planting season. The Tarver invention compresses the furrow shape just prior to or during planting, to eliminate uneven soil. Koch describes corn planted in 30-inch rows with application of insecticides and liquid nitrogen fertilizer. There is a legume ground cover such as vetch or clover. According to this report, clover did not demonstrate potential as a perennial cover crop. Phillip Koch, “Legume Cover Crops for No-Till Corn” in J. F. Power, THE ROLE OF LEGUMES IN CONVERSATION TILLAGE SYSTEMS (1984).
Decker et al. describes winter legume cover crops which were seeded after fall corn harvests, and which were allowed to grow until corn planting the following spring. His results indicated that fall-seeded legumes at least partially replace artificial nitrogen fertilizers for maximum corn yields. A. M. Decker et al., “Fall Seeded Legumes' Nitrogen Contributions to No-Till Corn Production,” in J. F. Power, supra.
Holderbaum reported results in which legumes were grown prior to corn, but later during the same growing season. In this model the legumes were clover and rye grass. According to this investigation, subsequent corn grain yields were highest when the cover crop was not removed. J. F. Hauderbaum et al., “Forage contributions for winter legume cover crops in no-till crop production,” in J. F. Power, supra.
Scott and Burt reported intercropping red clover into corn seedlings when the corn seedlings were approximately six to twelve inches high. The scientists applied chemical herbicides to the seedlings during this investigation. According to Scott and Burt, they consistently obtained good crops by cultivating corn in 30-inch intercropped rows. High corn yields also consistently occurred following the plowdown of one year of red clover hay. Scott and Burt concluded that red clover or other legume establishment by intercropping into corn might become a beneficial management approach for nitrogen replenishment, organic matter addition and reduced erosion. T. W. Scott and Robert F. Burt, “Use of Red Clover in Corn Polyculture Systems,” in J. F. Power, supra.
Paudey and Pendleton reported the planting of corn seed in 1.5 meter rows with corn seedlings spaced approximately 17 centimeters apart. Three rows of soybeans were planted between single rows of corn. The investigators applied herbicides and pesticides to the seedlings during the experiments. Forty-two days after planting, the two most exterior soybean rows were plowed into the cornrows in a traditional ‘hilling up’ procedure. R. K. Paudey and J. W. Pendleton, “Soybeans as a Green Manure in a Maize Intercropping System,” EXPERIMENTAL AGRICULTURE 22:178-85 (1986).
Eadie et al. reported the effect of cereal cover crops upon weed control. The investigators hand planted cereal seed within plots which were approximately 2.3 meters wide and 8.0 meters long. The rows were approximately at 0.75 meter equidistantly spaced intervals. These investigators seeded the cereal cover crops immediately after the ridging cultivation at the 11-12 leaf stage of corn plants. According to the Eadie report, corn grain yields remained unchanged by cover crops seeded at the 11-12 leaf stage of corn, compared to bare soil treatment controls. Allan G. Eadie et al., “Integration of Cereal Cover Crops in a Ridge-Tillage Corn Production,” WEED TECHNOLOGY 6 (3) (July-September 1992).
Lesoing and Francis stripcropped corn and soybeans to reduce erosion in eastern Nebraska from 1988 to 1990. Corn and soybeans were no-till planted in a north-south orientation in alternating 6.1 meter wide strips (eight rows, 0.76 meter between rows). Each row was approximately 46 meters in length, and each experimental planting areas comprised approximately 280 square meters. Lesoing and Francis planted corn seed at a density of approximately 66,250 seeds/ha. Between the corn strips they planted soybean seedlings in strips of eight rows at 475,000 seeds/ha.
According to this study, corn border row yields next to soybeans increased significantly compared with interior rows. These scientists suggested that water stress, light quality and shading are among the factors which affect crop yields at different stages of crop development. Gary W. Lesoing and Charles A. Francis, “Strip Intercropping Effects on Yield and Yield Components of Corn, Grain, Sorghum and Soybean,” AGRONOMY J. 91: 807-13 (1999).
At least one farmer has reported that closer planting of crops in rows results in more equitable distribution of sunlight, soil moisture and nutrients. NO TILL FARMER (mid-January 1986).